1. Field of the Invention
The present invention relates generally to the art of coverings for doors and windows, and more particularly to the preparation of vanes which may be used for such door or window coverings. In its most preferred embodiment, the present invention relates to novel vane structures which include a rigid and hollow vane prepared from a fibrous batt which is thermally transformed into a polymer matrix at least partially enveloping fibers. The present invention relates to the use of such vanes which are treated on their exterior surface to provide a decorative appearance or to such vanes which have a fabric layer bonded to an exterior surface. The present invention also relates to a method of making such rigid, hollow vanes.
2. Description of the Prior Art
A wide variety of coverings for doors and windows are known to the art. These include very old products such as roller shades and venetian-type blinds, as well as the newer types of xe2x80x9csoftxe2x80x9d window coverings, including pleated and cellular blinds and shades, various light control products, Roman shades, and fabric covered vertical blinds. The latter typically include a track which extends across an opening to be covered, with trucks mounted in the track for movement by a wand device or by cords and pulleys. Vanes are attached to the truck and are pivotable about a longitudinal axis of the vanes to open them to a first position which permits light to enter a room and to a second position in which the vanes overlie one another, in which case privacy is achieved. Moreover, light weight sheer fabric sheets have been attached to thin, rigid vanes to achieve a xe2x80x9cblind with curtainxe2x80x9d product, one of which is described in U.S. Pat. No. 5,638,881 issued to Ruggles, et al. on Jun. 17, 1997 and entitled xe2x80x9cBlind With Curtainxe2x80x9d, which patent is assigned to the assignee of the present invention.
Recently, a number of such vertical blind products have been proposed which include hollow, tubular fabric vanes. These can include stiffening compounds to ensure that the bottom rotates the same amount as the top, with no twist in the top to bottom relationship, to achieve an aesthetically pleasing product. It has also been proposed that such vanes have a cross-section simulating an air foil. These known vanes are preferably made from a material having diagonal, dimensional stability or memory so that they resist stretching in a longitudinal direction. It is also known that with such vanes, a reinforcing strip can be applied to an open end of the vane to provide a positive and durable attachment for supporting the vane from an operating system. Patents describing such vanes include U.S. Pat. No. 5,797,442 issued Aug. 25, 1998 to Colson, et al. for xe2x80x9cVanes For Architectural Covering And Method Of Making Samexe2x80x9d and U.S. Pat. No. 5,960, 850 issued on Oct. 5, 1999 to Colson, et al. for xe2x80x9cVane For An Architectural Coveringxe2x80x9d.
The vanes used in one embodiment in the aforementioned Colson, et al. patent have a cross-sectional configuration best illustrated in FIG. 6B of the ""442 patent, i.e. one resembling an air foil. Various techniques are described for ensuring that the shape is maintained, such as the use of stiffening compounds, or in the embodiment shown in FIG. 12, the use of a resilient rubber strip along the inside of the blunt end of the vane. Various single and double thickness vanes, and further vane structures, are disclosed in PCT International Application No. W096/35881 to the same inventors, which application claims priority to the parent application of the aforementioned ""442 Colson, et al. patent.
FIG. 1 of the Colson, et al. patent discloses a vertical arrangement in which a plurality of the vanes are suspended from a track 30 and are pulled across the opening to be covered using a wand. The vanes may be rotated to an open, light-admitting position as shown in FIG. 1, or to a privacy position as shown in FIG. 3. If the vane is constructed from transparent or sheer materials, light can be emitted in a diffused pattern into the room when the vanes are in the closed position, as illustrated in FIG. 4 of this patent. An important characteristic of this patent series, however, is that the material used for the vanes be flexible, even in embodiments which are described as xe2x80x9claminatesxe2x80x9d, where a functional interior layer is applied to a decorative exterior layer. There is no teaching or suggestion in the Colson, et al. patent family of using such air foil vanes in horizontal systems, as would be predicted since the flexible nature of the vanes would cause the vanes to sag and destroy the aesthetics thereof.
The assignee of the present invention has filed an application for a xe2x80x9cFoam Core Vane For Door And Window Coveringxe2x80x9d, on Aug. 10, 1999 in the name of Bryan K. Ruggles and granted Ser. No. 09/371,226. In this application, hollow vanes are filled with a foam material, such as urethane and polyisocyanurate foams, to cause the vanes to be sufficiently rigid to allow them to be used in a variety of door and window coverings. A polymeric foam is placed inside of a fabric sleeve in a mold which fills to the desired air foil cross-sectional shape when the foam expands. This patent application mentions the use of the foam core vanes in horizontal systems.
While new window coverings are shown in these various aforementioned patents and applications, including a variety of different and useful door and window coverings employing foil shaped vanes, it would be desirable to provide such vanes in a rigid configuration which provide thermal benefits (a feature provided by the foam core vanes), as well as greater structural integrity and resistance to damage in more severe end use applications. It would also be desirable to provide vanes heretofore used principally for vertical blind applications in various horizontal configurations.
A primary feature of the present invention is to provide a new, hollow and rigid vane for door and window coverings.
Another feature of the present invention is to provide methods for manufacturing new, hollow and rigid vanes for door and window coverings.
A different feature of the present invention is to provide improved vanes for door and window coverings which may be hung horizontally or vertically.
Another feature of the present invention is to provide vanes for door and window coverings which have high insulation characteristics when the vanes are in a position in which they overlap one another.
Yet another feature of the present invention is to provide vanes for door or window coverings which may include a wide variety of exterior covering materials.
How the foregoing and other features of the present invention are accomplished will be described in the following detailed description of the preferred and alternate embodiment, taken in conjunction with the FIGURES. Generally, however, the features are provided in a vane which, in the most preferred embodiment has a cross-section that is generally in the shape of an air foil and which includes a rigid component prepared from a felt batt which includes at least two types of fibrous material. A first fiber has a lower melting point than the remaining fibers in the batt. The shell of the vane of the present invention is formed by thermally treating the batt at a temperature above the melting point of the low melt component, so that a polymer matrix is formed which at least partially envelopes the high melt fibers. The vanes may be manufactured by placing the batt material into a mold and thermally treating the batt while compressing the batt to form the polymer matrix. If the shell of the vane is to be covered by a fabric for decorative or other purposes, the fabric is preferably adhered to the batt prior to the thermal treating and molding operations. Alternatively, the fabric can be added after the shell has been formed. An adhesive may be used to apply the fabric to the shell at whatever stage in the process it is applied. The vanes, after leaving the mold, are cooled and cut into the desired length by a cutting means, such as a rotating knife, and are further converted for the particular end use. The features are also accomplished using preferred and described hanger systems, edge trimming processes, end caps to enhance thermal properties and vane shapes which enhance the light blocking properties of a finished system. Other ways in which the above and other features of the invention are accomplished will become apparent to those skilled in the art after they have read the remainder of this specification, such other ways falling within the scope of the present invention if they fall within the scope of the claims which follow.